Central venous system access in a patient is an important aspect of administering intravenous therapy, such as drug, chemotherapy, and total parenteral nutrition (TPN). It is desirable that the therapy be administered in the superior vena cava (SVC) of the central venous system. In order to gain access, introducer devices are commonly used, through which other medical devices, such as central venous catheters (CVC), are inserted. One such example of a CVC is a peripherally inserted central catheter (PICC). A PICC typically has one or more tubes, which are externally accessible by a clinician, that converge into a single catheter body that is internally implanted in a vein of the patient. The tubes are adapted to receive therapeutic agents, which are then released through a distal tip of the catheter body into the central venous system of the patient.
The most common technique used by the clinician to gain access to the central venous system of the patient with a PICC is a modified Seldinger technique. This technique involves the clinician first inserting a needle through the patient's skin at a peripheral location and into a vein to form a venotomy. The clinician then inserts the guidewire through the passageway of the needle and into the vein. The distal end of the guidewire may then be translated to the target site. Next, the clinician removes the needle from the proximal end of the guidewire, and following removal of the needle the clinician inserts an introducer device and dilator assembly over the proximal end of the guidewire and into the vein. The introducer device and dilator assembly typically includes a splittable introducer device and a dilator to facilitate the ease of insertion and creation of a larger opening in the venotomy. The clinician then removes the dilator, and may even subsequently remove the guidewire from the lumen of the introducer device, leaving the introducer device inserted in the body. The clinician usually with the use of the guidewire determines a suitable length of the PICC and then trims the PICC accordingly.
Next, with reference to FIG. 1, a PICC 8 is inserted through introducer device 10 in order to gain access to the vein and eventually the SVC of the central venous system. PICC 8 has a catheter body 9 extending from a manifold 11, with a portion 12 of catheter body 9 adjacent manifold 11 shown to be tapered. PICC 8 is shown inserted through a constant diameter passageway 13 of introducer device 10. As can be seen, the constant diameter passageway 13 is only sized to receive most of catheter body 9 of PICC 8, essentially until the size of the catheter body at tapered portion 12 is greater than the size of passageway 13. As a result, tapered portion 12 is left dangling external to a handle 14 of introducer device 10. This arrangement is problematic because the dangling tapered portion 12 (about 10-15 cm) can result in an increase in patient discomfort at the access site.
Furthermore, the distal tip of PICC 8 is initially positioned short of its preferred target site by about the same amount as the length of the dangling tapered portion 12. The preferred target site to position a distal tip of a PICC is the lower one-third of the SVC, close to the junction of the SVC and the right atrium. At this location, it has been found that complications from thrombosis and infection are considerably reduced. One factor for this reduction is the ability of the distal tip of the PICC to float freely within the vein lumen at this location and to lie parallel to the vein wall without impinging on the wall. Any impinging of the vein wall from the PICC is known to cause irritation, if not damage, to the vein wall.
Since the distal tip of PICC 8 is not initially positioned at its preferred target site, the clinician must then perform a series of alternating steps of peeling a small part of introducer device 10 away from the implanted PICC 8 and translating the distal tip of PICC 8 closer to the target site until the distal tip of the PICC is at the preferred target site. However, when performing the series of alternating steps, the clinician must manipulate tapered portion 12 of catheter body 9 of PICC 8, leaving the catheter body along this portion highly susceptible to buckling and kinking. Not until the clinician is satisfied with the location of the distal tip of the PICC does this risk of buckling reduce. Buckling and kinking of PICC 8 is highly undesirable because the PICC becomes essentially useless for its intended purpose. At that point, a new PICC must be inconveniently reinserted into the vein by starting over at the very beginning with the modified Seldinger technique, which can extend the procedure time and further delay the administration of intravenous therapy.
Thus, what is needed is an introducer device that is configured to receive a catheter to permit the distal tip of the catheter to reach a target site, e.g., the central venous system, during its initial insertion through the introducer device. Further, what is needed is an introducer device that is configured to receive a catheter to limit, if not eliminate, any external dangling portion of the catheter and its associated risks to buckling and/or kinking during insertion through the introducer device. What is also needed is a catheterization system, and method of use thereof for therapeutic treatment, such as therapeutic treatment of the central venous system, that can cause less discomfort and inconvenience to the patient.